Fluid drop ejectors have been developed for inkjet printing. Nozzles which allow the formation and control of small ink droplets permit high resolution, resulting in printing sharper characters and improved tonal resolution. Drop-on-demand inkjet printing heads are generally used for high-resolution printers. In general, drop-on-demand technology uses some type of pulse generator to form and eject drops. In one example, a chamber having a nozzle orifice is fitted with a piezoelectric wall which is deformed when a voltage is applied. As a result of the deformation, the fluid is forced out of the nozzle orifice and impinges directly on an associated printing surface. Another type of printer uses bubbles formed by heat pulses to force fluid out of the nozzle orifice.
There is a need for an improved fluid drop ejector for use not only in printing, but also, for photoresist deposition in the semiconductor and flat panel display industries, drug and biological sample delivery, delivery of multiple chemicals for chemical reactions, DNA sequences, and delivery of drugs and biological materials for interaction studies and assaying. There is also need for a fluid ejector that can cover large areas with little or no mechanical scanning.
Various types of ultrasonic transducers have been developed for transmitting and receiving ultrasound waves. These transducers are commonly used for biochemical imaging, non-destructive evaluation of materials, sonar, communication, proximity sensors and the like. Two-dimensional arrays of ultrasound transducers are desirable for imaging applications. Making arrays of transducers by dicing and connecting individual piezoelectric elements is fraught with difficulty and expense, not to mention the large input impedance mismatch problem that such elements present to transmit/receiving electronics.
Scanning force microscopes have been applied to many kinds of samples which cannot be imaged by the other scanning probe microscopes. Indeed, they have the advantage of being applicable to the biological science field where, in order to image living biological samples, the development of scanning force microscopes in liquid with minimum heat production specification is needed. In addition, non-contact scanning force microscopes operating in liquid would permit imaging soft and sensitive probe lithography and high density data storage. Two dimensional arrays of atomic force probes with self-exciting piezoelectric sensing would provide a scanning force microscope which would meet the identified needs.